PROJECT SUMMARY/ABSTRACT Consistent with NINR and NCMRR priorities to address sleep disorders in the context of rehabilitation, this proposal aims to evaluate the efficacy of a nonpharmacological intervention for insomnia among older patients recovering from hip or knee arthroplasty. Almost half of the 15 million older patients hospitalized each year report disrupted sleep during their hospital visit. Sleep complaints can persist for several months following hospitalization and are associated with functional impairment during and following discharge. Further, daytime sequela of insomnia, such as diminished attention/concentration and fatigue, may serve to undermine and limit the effectiveness of rehabilitation. Thus, the proposed study aims to evaluate a much-needed safe treatment for insomnia (cognitive behavioral therapy for insomnia) in conjunction with medical rehabilitation to manage insomnia symptoms and promote functional health. Improving sleep is expected to enhance rehabilitation, by increasing patients' abilities to attend and adhere to rehabilitation recommendations. To maximize the public health impact, improve access, and reduce treatment barriers (stigma and transportation issues), we propose to evaluate the efficacy and effectiveness of the intervention delivered by nurses and physical and occupational therapists hospital bedside and in the home environment. The central hypothesis is that tailored CBTI delivered during and following hospitalization will improve sleep and functional outcomes in older adults receiving medical rehabilitation and is guided by the following aims: (1) to evaluate the efficacy of CBTI in a randomized, placebo-controlled trial, and (2) to determine the effectiveness of CBTI on rehabilitation and health outcomes. Primary outcomes, for which the study is optimally designed and sufficiently powered, are subjectively- and objectively-measured sleep. Secondary outcomes, for which we are unable to estimate power are functional (motor, cognition, independence) outcomes. We will also explore the relationship of treatment response to other health outcomes, including level of inflammation, medication use, fatigue, pain intensity, and depressive symptom severity. Our team has extensive experience in designing and implementing behavioral health clinical trials for older adults within hospital and community-based settings. If effective the sleep intervention has the potential to optimize functional gains in rehabilitation and reduce adverse health outcomes, thereby improving quality of life and reducing significant costs to society.